# Dwarfs

Four dwarfs would prepare firewood for Snow White in580 minutes. After an hour and a half they recruit friends so that finished preparing the wood for 280 minutes. How many dwarfs they recruited?

Result

x =  3

#### Solution:

1.5*60*4 + 280*(x+4) = 580*4

280x = 840

x = 3

Calculated by our simple equation calculator.

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